Method for producing deposition mask, deposition mask, and method for producing organic semiconductor device

ABSTRACT

A method for manufacturing a vapor deposition mask including a resin layer, and a magnetic metal body formed on the resin layer, the method including the steps of: (A) providing a magnetic metal body having at least one first opening; (B) providing a substrate; (C) forming a resin layer by applying a solution including a resin material or a varnish of a resin material on a surface of a substrate, and then performing a heat treatment thereon; (D) securing the resin layer formed on the substrate on the magnetic metal body so as to cover the at least one first opening; (E) forming a plurality of second openings in a region of the resin layer that is located in the at least one first opening of the magnetic metal body; and (F) after the step (E), removing the substrate from the resin layer.

TECHNICAL FIELD

The present invention relates to a method for manufacturing a vapordeposition mask, and particularly to a method for manufacturing a vapordeposition mask having a structure in which a resin layer and a metallayer are layered together. The present invention also relates to avapor deposition mask, and a method for manufacturing an organicsemiconductor device using a vapor deposition mask.

BACKGROUND ART

In recent years, organic EL (Electro Luminescence) display devices havebeen drawing public attention as a display of the next generation. Withorganic EL display devices that are currently mass-produced, theformation of an organic EL layer is primarily done by using a vacuumvapor deposition method.

Typically, a mask made of a metal (a metal mask) is used as the vapordeposition mask. However, with the increasing definition of organic ELdisplay devices, it is becoming difficult to precisely form a vapordeposition pattern using a metal mask. This is because it is difficultwith current metal processing techniques to precisely form smallopenings corresponding to a short pixel pitch (e.g., about 10 to 20 μm)in a metal plate (e.g., a thickness of about 100 μm) to be the metalmask.

In view of this, a vapor deposition mask (hereinafter referred to alsoas a “layered mask”) having a structure in which a resin layer and ametal layer are layered together has been proposed in the art as a vapordeposition mask for forming a vapor deposition pattern with a highdefinition.

For example, Patent Document No. 1 discloses a layered mask including aresin film layered with a hold member, which is a metal magnetic member.A plurality of openings corresponding to an intended vapor depositionpattern are formed in the resin film. Slits whose size is larger thanthe openings of the resin film are formed in the hold member. Theopenings of the resin film are arranged in the slits. Therefore, whenthe layered mask of Patent Document No. 1 is used, the vapor depositionpattern is formed corresponding to the plurality of openings of theresin film. Even small openings can be formed with a high precision in aresin film that is thinner than an ordinary metal plate used for a metalmask.

When forming small openings as described above in the resin film, alaser ablation method is suitably used. Patent Document No. 1 describesa method in which a resin film placed on a support member (e.g., a glasssubstrate) is irradiated with a laser so as to form openings of anintended size.

FIGS. 28(a) to 28(d) are schematic cross-sectional views eachillustrating a step of a conventional method for manufacturing a vapordeposition mask disclosed in Patent Document No. 1.

According to Patent Document No. 1, first, as shown in FIG. 28(a), ametal layer 82 having openings (slits) 85 therein is formed on a resinfilm 81, thereby obtaining a layered film 80. Then, as shown in FIG.28(b), the layered film 80 is attached to a frame 87 with tension in apredetermined in-plane direction(s) applied on the layered film 80.Then, the layered film 80 is placed on a glass substrate 90 as shown inFIG. 28(c). In this process, a surface of the resin film 81 that isopposite from the metal layer 82 is brought into close contact with theglass substrate 90 with a liquid 88 such as ethanol therebetween. Then,as shown in FIG. 28(d), portions of the resin film 81 that is exposedthrough the slits 85 of the metal layer 82 are irradiated with a laserbeam L, thereby forming a plurality of openings 89 in the resin film 81.Thus, a layered vapor deposition mask 900 is manufactured.

CITATION LIST Patent Literature

-   -   Patent Document No. 1: Japanese Laid-Open Patent Publication No.        2014-205870

SUMMARY OF INVENTION Technical Problem

However, with the conventional manufacturing method shown in FIG. 28, itmay be difficult to process the resin film with a high precision, andburrs may occur at the peripheral edge of the openings of the resinfilm.

When a resin film has burrs, it is difficult to bring a finished vapordeposition mask into close contact with a substrate to be the vapordeposition object (hereinafter referred to also as a “vapor depositionsubstrate”), and there may be a gap between the vapor deposition maskand the vapor deposition substrate. Thus, when a conventional vapordeposition mask is used, there is a possibility that a vapor depositionpattern having a high definition corresponding to the openings of thevapor deposition mask is not obtained. The details will be describedlater.

Note that although attempts have been made to remove burrs by wiping, orthe like, after a resin film is processed, no method has been proposedin the art that is capable of suppressing the occurrence of burrsitself.

The present invention has been made in view of the above, and an objectthereof is to provide a layered vapor deposition mask that can suitablybe used for forming a vapor deposition pattern having a high definition,and a method for manufacturing the same. Another object of the presentinvention is to provide a method for manufacturing an organicsemiconductor device using such a vapor deposition mask.

Solution to Problem

A method for manufacturing a vapor deposition mask in one embodiment ofthe present invention is a method for manufacturing a vapor depositionmask including a resin layer, and a magnetic metal body formed on theresin layer, the method including the steps of: (A) providing a magneticmetal body having at least one first opening; (B) providing a substrate;(C) forming a resin layer by applying a solution including a resinmaterial or a varnish of a resin material on a surface of the substrate,and then performing a heat treatment thereon; (D) securing the resinlayer formed on the substrate on the magnetic metal body so as to coverthe at least one first opening; (E) forming a plurality of secondopenings in the resin layer; and (F) after the step (E), removing thesubstrate from the resin layer.

In one embodiment, the step (E) is performed after the step (D); and theplurality of second openings are formed in a region of the resin layerthat is located in the at least one first opening of the magnetic metalbody.

In one embodiment, the step (E) is performed between the step (C) andthe step (D).

In one embodiment, the method further includes the step of providing aframe along a peripheral edge portion of the magnetic metal body.

In one embodiment, in the step (C), the heat treatment is performedunder such a condition that a tensile stress greater than 0.2 MPa isproduced on the resin layer at room temperature in a layer in-planedirection.

In one embodiment, a width of the at least one first opening is 30 mm ormore; and where δ denotes a maximum bend amount of a region of the resinlayer that is located in the at least one first opening of the magneticmetal body when the magnetic metal body is held in a horizontaldirection after the substrate is removed in the step (F), in the step(C), the heat treatment is performed under such a condition that atensile stress such that the maximum bend amount δ is 5 μm or less isproduced on the resin layer.

In one embodiment, where W denotes a minimum width of the at least onefirst opening, and where δ denotes a maximum bend amount of a region ofthe resin layer that is located in the at least one first opening of themagnetic metal body when the magnetic metal body is held in a horizontaldirection after the substrate is removed in the step (F), in the step(C), the heat treatment is performed under such a condition that atensile stress such that δ/W is 0.01% or less is applied on the resinlayer.

In one embodiment, a compressive stress is applied on the magnetic metalbody from the resin layer after the substrate is removed in the step(F).

In one embodiment, the resin layer is a polyimide layer, and thesubstrate is a glass substrate; and the heat treatment in the step (C)includes a step of heating the substrate with a solution including theresin material or a varnish of the resin material applied thereon to atemperature of 300° C. or more and 600° C. or less at a rate of 30°C./min or more.

In one embodiment, the step (D) includes the steps of: (D1) forming anadhesive layer on a portion of the resin layer; and (D2) attaching theresin layer to the magnetic metal body with the adhesive layertherebetween.

In one embodiment, the adhesive layer is a metal layer; and the step(D2) is a step of welding the metal layer to the magnetic metal body,thereby attaching the resin layer to the magnetic metal body with themetal layer therebetween.

In one embodiment, a width of the at least one first opening is 30 mm ormore, and there is no magnetic metal on a region of the resin layer thatis located in the at least one first opening of the magnetic metal body.

In one embodiment, the magnetic metal body has an open mask structure.

A vapor deposition mask in one embodiment of the present inventionincludes: a frame; a magnetic metal body supported on the frame andincluding at least one first opening; a resin layer arranged on themagnetic metal body so as to cover the at least one first opening; andan adhesive layer located between the resin layer and the magnetic metalbody for attaching together the resin layer and the magnetic metal body,wherein: the resin layer has a tensile stress in a layer in-planedirection; and the magnetic metal body receives a compressive stress inan in-plane direction from the resin layer.

In one embodiment, the tensile stress of the resin layer at roomtemperature is greater than 0.2 MPa.

In one embodiment, the adhesive layer is a metal layer fixed on theresin layer, and the metal layer is welded to the magnetic metal body.

In one embodiment, a width of the at least one first opening is 30 mm ormore; and a maximum bend amount δ of a region of the resin layer that islocated in the at least one first opening of the magnetic metal bodywhen the magnetic metal body is held in a horizontal direction is 5 μmor less.

In one embodiment, δ/W is 0.01% or less, where W denotes a width of theat least one first opening, and δ denotes a maximum bend amount of aregion of the resin layer that is located in the at least one firstopening of the magnetic metal body when the magnetic metal body is heldin a horizontal direction.

In one embodiment, a width of the at least one first opening is 30 mm ormore, and there is no magnetic metal on a region of the resin layer thatis located in the at least one first opening of the magnetic metal body.

In one embodiment, the magnetic metal body has an open mask structure.

A method for manufacturing an organic semiconductor device in oneembodiment of the present invention includes the step ofvapor-depositing an organic semiconductor material on a work using anyof the vapor deposition masks set forth above.

Advantageous Effects of Invention

An embodiment of the present invention provides a layered vapordeposition mask that can suitably be used for the formation of a vapordeposition pattern having a high definition, and a method formanufacturing the same.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1(a) is a plan view schematically showing a vapor deposition mask100 according to an embodiment of the present invention, and FIG. 1(b)is a cross-sectional view taken along line A-A of FIG. 1(a).

FIGS. 2(a) and 2(b) are plan views schematically showing another vapordeposition mask according to an embodiment of the present invention.

FIGS. 3(a) and 3(b) are a plan view and a cross-sectional view,respectively, illustrating a step of a method for manufacturing a vapordeposition mask according to an embodiment of the present invention.

FIGS. 4(a) and 4(b) are a plan view and a cross-sectional view,respectively, illustrating a step of a method for manufacturing a vapordeposition mask according to an embodiment of the present invention.

FIGS. 5(a) and 5(b) are a plan view and a cross-sectional view,respectively, illustrating a step of a method for manufacturing a vapordeposition mask according to an embodiment of the present invention.

FIGS. 6(a) and 6(b) are a plan view and a cross-sectional view,respectively, illustrating a step of a method for manufacturing a vapordeposition mask according to an embodiment of the present invention.

FIGS. 7(a) and 7(b) are a plan view and a cross-sectional view,respectively, illustrating a step of a method for manufacturing a vapordeposition mask according to an embodiment of the present invention.

FIGS. 8(a) and 8(b) are diagrams each schematically showing therelationship between the stress caused by a film formed on a substrateand the deformation of the substrate.

FIGS. 9(a) to 9(e) are cross-sectional views each showing a step ofanother method for manufacturing a vapor deposition mask according to anembodiment of the present invention.

FIGS. 10(a) to 10(e) are cross-sectional views each showing a step ofanother method for manufacturing a vapor deposition mask according to anembodiment of the present invention.

FIGS. 11(a) to 11(e) are cross-sectional views each showing a step ofstill another method for manufacturing a vapor deposition mask accordingto an embodiment of the present invention.

FIG. 12 is a top view showing Samples A to C.

FIGS. 13(a) and 13(b) are a plan view and a cross-sectional view,respectively, showing a vapor deposition mask of Example 1.

FIGS. 14(a) and 14(b) are plan views each showing the scan direction ina bend measurement.

FIGS. 15(a) to 15(c) are graphs each showing the change in the height ofthe polyimide film of a cell C1 in a vapor deposition mask of Example 1.

FIGS. 16(a) to 16(c) are graphs each showing the change in the height ofthe polyimide film of the cell C1 in the vapor deposition mask ofExample 1.

FIGS. 17(a) to 17(c) are graphs each showing the change in the height ofthe polyimide film of a cell C2 in the vapor deposition mask of Example1.

FIGS. 18(a) to 18(c) are graphs each showing the change in the height ofthe polyimide film of the cell C2 in the vapor deposition mask ofExample 1.

FIGS. 19(a) to 19(c) are graphs each showing the change in the height ofthe polyimide film of a cell C3 in the vapor deposition mask of Example1.

FIGS. 20(a) to 20(c) are graphs each showing the change in the height ofthe polyimide film of the cell C3 in the vapor deposition mask ofExample 1.

FIGS. 21(a) to 21(c) are graphs each showing the change in the height ofthe polyimide film of a cell in a vapor deposition mask of Example 2.

FIGS. 22(a) to 22(c) are graphs each showing the change in the height ofthe polyimide film of the cell in the vapor deposition mask of Example 1

FIGS. 23(a) and 23(b) show vapor deposition masks of Examples 1 and 2,respectively.

FIG. 24 is a cross-sectional view schematically showing an organic ELdisplay device 500 of a top emission type.

FIGS. 25(a) to 25(d) are cross-sectional views each showing a step inthe process of manufacturing the organic EL display device 500.

FIGS. 26(a) to 26(d) are cross-sectional views each showing a step inthe process of manufacturing the organic EL display device 500.

FIGS. 27(a) to 27(d) are schematic cross-sectional views illustratinghow a burr is produced on a resin film with a laser ablation method.

FIGS. 28(a) to 28(d) are schematic cross-sectional views eachillustrating a step in a conventional method for manufacturing a vapordeposition mask disclosed in Patent Document No. 1.

DESCRIPTION OF EMBODIMENTS

With a conventional method for manufacturing a layered vapor depositionmask, burrs may be produced at the peripheral edge of the openings ofthe resin film, as described above. The present inventors conducted anin-depth study on how burrs are produced, arriving at the findings asfollows.

With the conventional method, as described above with reference to FIGS.28(c) and 28(d), the openings 89 are formed by irradiating predeterminedregions (hereinafter referred to as “laser irradiation regions”) of theresin film 81 with the laser beam L while the resin film 81 is kept inclose contact with the glass substrate 90 because of the surface tensionof the liquid 88 such as ethanol. Based on a study by the presentinventors, it was found that with this method, bubbles are producedpartially at the interface between the glass substrate 90 and the resinfilm 81 when bringing the resin film 81 into close contact with theglass substrate 90, thereby locally lowering the adhesion. Moreover, thepresent inventors found that when there is a bubble under a certainlaser irradiation region of the resin film 81, it does not only make itdifficult to form the openings 89 with a high precision but it alsomakes it likely that a burr is produced in that laser irradiationregion. This will be described in detail with reference to FIG. 27.

FIGS. 27(a) to 27(d) are schematic cross-sectional views illustratinghow a burr is produced because of a bubble between the glass substrate90 and the resin film 81. FIG. 27 does not show the metal layer and theliquid.

As shown in FIG. 27(a), when the resin film 81 is brought into closecontact on a support member such as the glass substrate 90 (e.g., with aliquid therebetween), a gap (bubble) 94 may be produced partiallybetween the glass substrate 90 and the resin film 81. When a process onthe resin film 81 using a laser ablation method (hereinafter referred toalso simply as “laser process”) is performed in this state, a laserirradiation region 92 for forming an opening may be placed in a portionof the resin film 81 that is located over the bubble 94, as shown inFIG. 27(b). The laser irradiation region 92 is irradiated in a pluralityof shots while focusing on the surface of the resin film 81, forexample.

Laser ablation refers to a phenomenon in which when the surface of asolid is irradiated with a laser beam, a constituent substance on thesolid surface rapidly radiates because of the energy of the laser beam.Herein, the speed of radiation is referred to as the ablation speed. Ina laser process, there may be an ablation speed distribution dependingon the energy distribution across the laser irradiation region 92 sothat a through hole is formed first only in a portion of the resin film81. Then, as shown in FIG. 27(c), another portion 98 of the resin film81 that has been thinned is folded back onto the reverse side of theresin film 81 (i.e., into the bubble 94 between the resin film 81 andthe glass substrate 90), and the portion 98 is no longer irradiated withthe laser beam L. As a result, the opening 89 is formed with the thinnedportion 98 remaining unremoved. In the present specification, theportion 98 of the resin film 81 that is thinned and left remaining isreferred to as a “burr”.

With the burr 98 projecting on the reverse side of the resin film 81,when the vapor deposition mask is placed on a vapor depositionsubstrate, a portion of the vapor deposition mask may be lifted off thevapor deposition substrate. Then, there is a possibility that a vapordeposition pattern that is shaped corresponding to the openings 89 maynot be obtained.

Note that a process of removing the burr 98 of the resin film 81 (a burrremoving step) may be performed after the laser process. For example,attempts have been made to wipe the reverse surface of the resin film81, for example. However, it is difficult, by a burr removing step, toentirely remove the burr 98 on the resin film 81. As shown in FIG.27(d), wiping may possibly move back some burrs 98 so as to protrudeinto the opening 89, thereby causing shadowing during a vapor depositionstep.

Based on the findings described above, the present inventors found anovel method with which it is possible to form, with a high precision,openings of an intended size in a resin layer supported on a supportmember while suppressing the occurrence of burrs, thus arriving at thepresent invention.

An embodiment of the present invention will now be described withreference to the drawings. Note that the present invention is notlimited to the following embodiment.

Embodiment

<Structure of Vapor Deposition Mask>

Referring to FIGS. 1(a) and 1(b), a vapor deposition mask 100 accordingto an embodiment of the present invention will be described. FIGS. 1(a)and 1(b) are a plan view and a cross-sectional view, respectively,schematically showing the vapor deposition mask 100. FIG. 1(b) shows across section taken along line A-A of FIG. 1(a). Note that FIG. 1schematically shows an example of the vapor deposition mask 100, and itis needless to say that the size, number, arrangement, length ratio,etc., of the various components are not limited to those shown in thefigure. This similarly applies also to other figures to be referred tobelow.

As shown in FIGS. 1(a) and 1(b), the vapor deposition mask 100 includesa magnetic metal body 20, a resin layer 10 arranged on a primary surface20s of the magnetic metal body 20. It may further include an adhesivelayer 50 located at least partially between the resin layer 10 and themagnetic metal body 20. The adhesive layer 50 is a layer that bondstogether the resin layer 10 and the magnetic metal body 20.

The vapor deposition mask 100 is a layered mask having a structure inwhich the resin layer 10 and the magnetic metal body 20 are layeredtogether. Hereinafter, a layered member 30 including the resin layer 10and the magnetic metal body 20 may be referred to as a “mask member”.

A frame 40 may be provided along the peripheral edge portion of the maskmember 30. The frame 40 may be attached to a surface of the magneticmetal body 20 that is opposite from the primary surface 20s.

The magnetic metal body 20 includes at least one opening (hereinafterreferred to as a “first opening”) 25. In this example, the magneticmetal body 20 has six first openings 25. A portion 21 of the magneticmetal body 20 located around the first openings 25 and where a metalexists (including a portion between adjacent first openings 25) isreferred to as a “solid portion”.

The magnetic metal body 20 may have an open mask structure. An “openmask structure” refers to a structure in which a vapor deposition maskused for forming a plurality of devices (e.g., organic EL displays) onone vapor deposition substrate, wherein the vapor deposition mask hasone opening for a unit region U that corresponds to one device. Notethat the magnetic metal body 20 does not need to have an open maskstructure, and may have a structure in which two or more openings (e.g.,slits) are arranged for one unit region U, for example. Hereinafter, amagnetic metal body having an open mask structure may be referred tosimply as an “open mask”.

As will be described later, when performing a vapor deposition stepusing the vapor deposition mask 100, the vapor deposition mask 100 isarranged so that the magnetic metal body 20 is located on the vapordeposition source side and the resin layer 10 on the work (vapordeposition object) side. Since the magnetic metal body 20 is a magneticmember, the vapor deposition mask 100 can be easily held and secured onthe work in the vapor deposition step by using a magnetic chuck.

The resin layer 10 is arranged on the primary surface 20s of themagnetic metal body 20 so as to cover the first openings 25. A region 10a of the resin layer 10 that is located in the first opening 25 isreferred to as the “first region”, and a region 10 b thereof thatoverlaps a solid portion 21 of the magnetic metal body 20 as seen from adirection normal to the vapor deposition mask 100 is referred to as the“second region”.

A plurality of openings (hereinafter “second openings”) 13 are formed inthe first region 10 a of the resin layer 10. The plurality of secondopenings 13 are formed with a size, shape and position corresponding tothe vapor deposition pattern to be formed on the work. In this example,a plurality of second openings 13 are arranged in an array with apredetermined pitch in each unit region U. The interval between twoadjacent unit regions U is typically larger than the interval betweentwo adjacent second openings 13 in a unit region U. In this example,there is no magnetic metal on the first region 10 a.

The second region 10 b of the resin layer 10 is attached to the areaaround the first opening 25 of the magnetic metal body 20 (the solidportion 21) with the adhesive layer 50 therebetween. There is noparticular limitation on the adhesive layer 50, but the adhesive layer50 may be a metal layer. For example, the resin layer 10 may be attachedto the magnetic metal body 20 by forming a metal layer, by plating, orthe like, on the second region 10 b of the resin layer 10, and weldingtogether the metal layer and the solid portion 21 of the magnetic metalbody 20. Alternatively, the adhesive layer 50 may be formed from anadhesive. Note that it is only required that the resin layer 10 beattached to the magnetic metal body 20 by the method shown above, and itmay not be attached directly to the frame 40.

As will be described later, the resin layer 10 is a layer that is formedby applying a solution including a resin material (e.g., a soluble-typepolyimide solution) or a solution including a precursor of a resinmaterial (e.g., a polyimide varnish) on a support substrate such as aglass substrate, and performing a heat treatment thereon. The heattreatment, as used herein, includes a heat treatment for performing abaking step (e.g., 100° C. or more) when a soluble-type polyimidesolution is used, and a heat treatment for performing a baking andcuring step (e.g., 300° C. or more) when a polyimide varnish is used.

In the present embodiment, the plurality of second openings 13 areformed by performing a laser process on the resin layer 10 on thesupport substrate. The support substrate and the resin layer 10 are inclose contact with each other with no (or little) bubble therebetween,thereby suppressing the occurrence of burrs in the laser process step onthe resin layer 10. Thus, the resin layer 10 of the present embodimentsubstantially has no burrs. Even when the resin layer 10 has burrs, thenumber of burrs (per unit area) is substantially lower as compared withconventional methods. The support substrate is removed from the resinlayer 10 after the second openings 13 are formed in the resin layer.

The resin layer 10 formed on the support substrate by the methoddescribed above may have a tensile stress (internal stress of tension)in the layer in-plane direction. Therefore, since it is possible toreduce the bend occurring in the first region 10 a of the resin layer 10after removing from the support substrate, it is possible to form avapor deposition pattern having a high definition on the work. Thetensile stress of the resin layer 10 can be controlled by the heattreatment condition, or the like, used when forming the resin layer 10on the support substrate, for example. The tensile stress of the resinlayer 10 is greater than 0.2 MPa, for example, at room temperature. Itis preferably 3 MPa or more. Then, it is possible to more effectivelyreduce the bend.

Typically, when forming a resin film on the support substrate by a heattreatment, the heat treatment is performed under such conditions thatthe residual stress on the resin film can be reduced as much aspossible. This is because an increase in the residual stress (tensilestress) on the resin film will cause problems such as warping of thesupport substrate, thereby lowering the shape stability and thereliability. In contrast, the present embodiment intentionally causes apredetermined tensile stress on the resin layer 10, thereby reducing thebend of the resin layer 10. This eliminates the need for a step ofstretching the resin layer 10, and it is possible to manufacture a vapordeposition mask with a reduced bend by an easier process.

Note that the resin layer 10 being on the support substrate may have astress distribution, but once the support substrate is removed, themagnitude of tensile stress on the resin layer 10 can be leveled to besubstantially uniform across the surface. Thus, a tensile stress of asubstantially constant magnitude can be realized across the first region10 a of the resin layer 10.

According to the present embodiment, since the resin layer 10 has apredetermined tensile stress, it is possible to reduce the bendoccurring in the resin layer 10 without arranging a metal film close tothe second openings 13 of the resin layer 10. This eliminates the needfor a patterning step of precisely patterning a metal film. Moreover, itis possible to increase the size of the first opening 25 of the magneticmetal body 20 while suppressing the occurrence of a bend, and it ispossible to use the magnetic metal body 20 having an open maskstructure, for example. This will be described in detail below.

With conventional vapor deposition masks, a layered film of a resin filmand a metal film (a magnetic metal film) (or a resin film) was securedon a frame while being stretched in a particular layer in-planedirection by means of a stretcher, or the like (hereinafter referred toas a “stretching step”). With such a layered mask, if the opening of themetal film was too large, it was possible that the resin film bent byvirtue of its own weight, and a vapor deposition pattern shapedcorresponding to the openings of the resin film might not be obtained.In view of this, with conventional methods, it was necessary to form aprecise metal pattern on a resin film, as proposed in Patent DocumentNo. 1, so as to arrange a metal film, which is a hold member, as closeas possible to the openings of the resin film. In contrast, according tothe present embodiment, an intended tensile stress can be caused on theresin layer 10 based on the process conditions when forming the resinlayer 10 on the support substrate. Since a tensile stress is caused onthe resin layer 10, separately from the magnetic metal body 20, it ispossible to more easily control the magnitude of the tensile stress onthe resin layer 10. Therefore, there is no need to form a magnetic metalfilm having a precise pattern on a resin film, and it is possible to usea metal plate pre-formed with first openings therein such as an openmask. Therefore, it is possible to significantly reduce themanufacturing process and the manufacturing cost as compared withconventional methods.

The present embodiment is particularly advantageous when using amagnetic metal body 20 having first openings 25 of a relatively largesize therein, such as an open mask, for example. Even when the size ofthe first openings 25 is relatively large, it is possible to reduce thebend occurring in the resin layer 10 because of the internal tensilestress of the resin layer 10. Therefore, there is no need to separatelyarrange a magnetic metal on the first region 10 a of the resin layer 10so as to suppress misalignment of a vapor deposition pattern due to abend. The width (the dimension along the width direction) of the firstopening 25 may be 30 mm or more, or 50 mm or more, for example. Whilethere is no particular limitation on the upper limit of the width of thefirst opening 25, it is possible to suppress an increase in the bendamount when it is 300 mm or less, for example.

According to the present embodiment, it is possible to suppress themaximum bend amount δ of the resin layer 10 to be less than or equal toa predetermined value δs. Herein, the maximum bend amount δ of the resinlayer 10 refers to the maximum bend amount of the first region 10 a ofthe resin layer 10 when the magnetic metal body 20 is held in thehorizontal direction. While there is no particular limitation on δs, itis 5 μm, preferably 2 μm, for example. For example, when the width ofthe first opening 25 of the magnetic metal body 20 is 30 mm or more, themaximum bend amount δ of the resin layer 10 may be 5 μm or less. Or, δ/Wmay be 0.01% or less, where W denotes the width of the first opening 25,and δ denotes the maximum bend amount of the resin layer 10.

With the vapor deposition mask 100 of the present embodiment, themagnetic metal body 20 receives a compressive stress in an in-planedirection from the resin layer 10. Note that when a layered film issecured on a frame by a stretching step, the metal film and the resinfilm both receive tension in a layer plane direction(s) from the frame,and a configuration in which the resin film gives a compressive stresson the metal film is not obtained. Also when only the resin film issecured on the frame by a stretching step, the resin film is not kept inclose contact with the metal film, and it is believed that the metalfilm does not receive a compressive stress from the resin film.

For example, polyimide can suitably be used as the material of the resinlayer 10. Polyimide is desirable in terms of strength, chemicalresistance and heat resistance. Other resin materials such aspolyparaxylene, bismaleimide and silica hybrid polyimide may be used asthe material of the resin layer 10. The linear thermal expansioncoefficient αR (ppm/° C.) of the resin film of the resin layer 10 ispreferably generally equal to the linear thermal expansion coefficientof the substrate, which is the vapor deposition object. Such a resinlayer 10 can be formed based on the formation conditions, etc., such asthe resin material and the curing conditions. The method for forming theresin layer 10 will be described later.

There is no particular limitation on the thickness of the resin layer10. Note however that if the resin layer 10 is too thick, portions ofthe vapor deposition film may be thinner than an intended thickness(this is called “shadowing”). In order to suppress the occurrence ofshadowing, the thickness of the resin layer 10 is preferably 25 μm orless. When it is 3 μm or more, it is possible to form a resin layer 10having a more uniform thickness by performing a heat treatment on asolution including a resin material (or a precursor thereof) applied onthe support substrate. Also in view of the strength and the cleaningtolerance of the resin layer 10 itself, it is preferred that thethickness of the resin layer 10 is 3 μm or more.

Various magnetic metal materials can be used as the material of themagnetic metal body 20. Materials having a relatively large linearthermal expansion coefficient αM such as Ni, Cr, ferritic stainlesssteel and martensitic stainless steel, for example, may be used, ormaterials having a relatively small linear thermal expansion coefficientαM such as an Fe-Ni-based alloy (invar) or an Fe-Ni-Co-based alloy, forexample, may be used.

Note that conventional vapor deposition masks such as that disclosed inPatent Document No. 1 are designed so that the size of slits of themetal layer is as small as possible, and the area ratio of the solidportion with respect to the entire mask is relatively high (over 70% inFIG. 1 of Patent Document No. 1). Therefore, a material having a smalllinear thermal expansion coefficient αM (e.g., αM: less than 6 ppm/° C.)was used as the material of the metal layer. This is to ensure the shapestability of the vapor deposition mask in the vapor deposition step. Incontrast, with the present embodiment, the area ratio of the solidportion 21 with respect to the entire mask can be made small (i.e., thearea ratio of the first openings 25 can be made large), and it istherefore possible to use a metal having a high linear thermal expansioncoefficient that cannot be used with conventional methods. Therefore,various metal materials can be used, irrespective of their linearthermal expansion coefficient, thus increasing the degree of freedom inselecting a metal material.

There is no particular limitation on the thickness of the magnetic metalbody 20. Note however that when the magnetic metal body 20 is too thin,the attraction force received for the magnetic field of the magneticchuck will decrease, and it will be difficult to hold the vapordeposition mask 100 on the work in the vapor deposition step. Therefore,it is preferred that the thickness of the magnetic metal body 20 is 5 μmor more.

It is preferred that the thickness of the magnetic metal body 20 is setwithin such a range that no shadowing occurs in the vapor depositionstep. With conventional vapor deposition masks, a metal layer, which isa hold member, was arranged close to the openings of the resin film.Therefore, the thickness of the metal layer needed to be small (e.g., 20μm or less) in order to suppress shadowing in the vapor deposition step.In contrast, according to the present embodiment, the resin layer 10 hasa predetermined tensile stress, and there is no need to arrange themagnetic metal body 20 close to the second openings 13 of the resinlayer 10. Therefore, the edge portion of the first opening 25 of themagnetic metal body 20 can be arranged sufficiently apart from thesecond openings 13 of the resin layer 10 (e.g., the minimum distanceDmin between the solid portion 21 of the magnetic metal body 20 and thesecond openings 13 is 1 mm or more). When the minimum distance Dmin islarge, shadowing is unlikely to occur even if the magnetic metal body 20is made thicker, thereby allowing the magnetic metal body 20 to be madethicker as compared with conventional methods. The thickness of themagnetic metal body 20 may be 1000 μm or more, for example, although italso depends on the vapor deposition angle, the taper angle of themagnetic metal body 20, and the minimum distance Dmin between the solidportion 21 of the magnetic metal body 20 and the second openings 13.When an open mask is used as the magnetic metal body 20, the thicknessof the open mask can be set to 300 μm or more, for example, by designingthe open mask so that the size of the first opening 25 is sufficientlylarger than the unit region U. While there is no particular limitationon the upper limit value of the thickness of the magnetic metal body 20,it is possible to suppress shadowing if it is 1.5 mm or less, forexample. Thus, according to the present embodiment, it is possible toincrease the degree of freedom in selecting the thickness, as well asthe material of the magnetic metal body 20.

The frame 40 is formed from a magnetic metal, for example.Alternatively, it may be formed from a non-metal material, e.g., a resin(plastic). With conventional vapor deposition masks, the frame wasrequired to have an adequate rigidity so that the frame would not bedeformed or broken by the tension from the layered film (a resin filmand a metal film) secured on the frame due to the stretching step.Therefore, a frame made of an invar having a thickness of 20 mm, forexample, was used. In contrast, according to the present embodiment,since the frame 40 is attached without performing the stretching step orwithout applying a large tension on the magnetic metal body 20, there isno tension on the frame 40 due to the stretching step. Therefore, it ispossible to use a frame 40 having a lower rigidity as compared withconventional methods, increasing the degree of freedom in selecting thematerial of the frame 40. It is also possible to make the frame 40thinner as compared with conventional methods. Using a frame that isthinner as compared with conventional methods or using a frame made of aresin, it is possible to obtain the vapor deposition mask 100 that has alight weight and a good handling property.

<Other Structure Examples of Vapor Deposition Mask>

FIGS. 2(a) and 2(b) are plan views schematically showing other vapordeposition masks 200 and 300 of the present embodiment. In thesefigures, like components to those of FIG. 1 are denoted by likereference signs. In the following description, only differences from thevapor deposition mask 100 will be described.

With the vapor deposition masks 200 and 300, the magnetic metal body 20includes a plurality of first openings 25 in the unit region U. Two ormore second openings 13 are located in each first opening 25 (needlessto say, the present invention is not limited to the number of secondopenings shown in the figure).

As shown in FIG. 2(a), the first openings 25 may be slits arranged inthe unit region U, wherein a slit is arranged for each column (or row)of second openings 13, which are arranged in an array extending in therow direction and the column direction. Alternatively, as shown in FIG.2(b), one first opening 25 may be arranged for each sub-area thatincludes a plurality of columns and a plurality of rows of secondopenings 13.

Note that while FIG. 1 and FIG. 2 illustrate vapor deposition maskshaving a plurality of unit regions U, the number of unit regions U andthe arrangement method therefor, the number of second openings 13 andthe arrangement method therefor in each unit region U are not limited tothe examples shown in the figures but are determined based on theconfiguration of the device to be manufactured. The number of unitregions U may be singular.

<Method for Manufacturing Vapor Deposition Mask>

Referring to FIG. 3 to FIG. 7, a method for manufacturing a vapordeposition mask of the present embodiment will be described using, as anexample, a method for manufacturing the vapor deposition mask 100. InFIG. 3 to FIG. 7, (a) and (b) are a plan view showing a step in anexample of a method for manufacturing the vapor deposition mask 100, anda cross-sectional view showing a step thereof taken along line A-A shownin (a).

First, as shown in FIGS. 3(a) and 3(b), a support substrate 60 isprovided, and the resin layer 10 is formed on the support substrate 60.For example, a glass substrate can suitably be used as the supportsubstrate 60. There is no particular limitation on the size andthickness of the glass substrate.

The resin layer 10 is formed as follows. First, a solution (e.g., apolyimide varnish) including a precursor of a resin material or asolution (e.g., a soluble-type polyimide solution) including a resinmaterial is applied on the support substrate 60. The method for applyinga solution may be a method known in the art such as a spin coatingmethod or a slit coater method. Herein, polyimide is used as the resinmaterial, and a solution (a polyimide varnish) including polyamic acid,which is a precursor of polyimide, is applied on the support substrate60 by a spin coating method. Then, a heat treatment (baking and curing)is performed to from a polyimide layer as the resin layer 10. The heattreatment temperature can be set to 300° C. or more, e.g., 400° C. ormore and 500° C. or less.

The heat treatment conditions are set so that a predetermined tensilestress is produced in the resin layer 10. For example, the conditionsmay be set so that a tensile stress greater than 0.2 MPa (preferably, 3MPa or more) is produced. The magnitude of tensile stress may varydepending on the thickness, shape and size of the support substrate 60,and the material properties (the Young's modulus, the Poisson's ratio,the thermal expansion coefficient, etc.) of the support substrate 60, aswell as the material of the resin layer 10 and the heat treatmentconditions. The heat treatment conditions as used herein include theheat treatment temperature (highest temperature), the heating speed, thehold time at a high temperature (e.g., 300° C. or more), the atmosphereduring the heat treatment, etc. The heat treatment conditions alsoinclude not only the temperature profile when heating but also thetemperature profile when cooling.

In order to leave a high tensile stress remaining in the resin layer 10,conditions may be set such that the polyimide varnish is caused toimidize rapidly, for example. As an example, it is possible to increasethe tensile stress by increasing the heating speed. For example, whenforming a polyimide layer on a glass substrate by a heat treatment, theglass substrate on which a polyimide varnish is applied may be heated toa temperature of 300° C. or more and 600° C. or less at a rate of 30°C./min or more. By setting the total amount of time for which the glasssubstrate is held at a temperature of 300° C. or more, for example,through the entire heat treatment step including heating and cooling toa short amount of time (e.g., within 30 min), it is possible to increasethe tensile stress to remain in the resin layer 10. Moreover, it ispossible to increase the tensile stress also by setting the total heattreatment time including heating and cooling to a relatively shortamount of time (e.g., within one hour), setting the hold time at thehighest temperature (standing time) to a short amount of time (e.g.,within 5 min), and rapidly cooling after reaching the highesttemperature, for example. There is no particular limitation on the heattreatment atmosphere, and it may be an air atmosphere or a nitrogen gasatmosphere. If a heat treatment is performed under a depressurizedatmosphere at 100 Pa or less, it is possible to more easily increase theheating speed.

Instead of a polyimide varnish, a solution including a solvent-solublepolyimide (polymer) (a soluble-type polyimide solution) may be appliedon the support substrate 60 and baked to form the resin layer 10. Whilethere is no particular limitation on the baking temperature, which maybe appropriately selected based on the boiling point of the solvent, itis 100° C. to 320° C., and preferably 120° C. to 250° C., for example.Also in such a case, it is possible to increase the tensile stress toremain in the resin layer 10 by increasing the heating speed to begenerally equal to that described above, and shortening the hold time ata high temperature.

When the resin layer 10 is formed on the support substrate 60, thesupport substrate 60 may be warped depending on the material andthickness of the support substrate 60. On the support substrate 60, theresin layer has a stress distribution. For example, the tensile stressincreases from the central portion toward the edge portion of the resinlayer 10. A greater tensile stress can possibly occur in the directionin which the support substrate 60 is longer.

Now, referring to FIG. 8(a) and FIG. 8(b), the relationship between thestress from a film RF formed on a substrate SUB and the deformation ofthe substrate SUB. As schematically shown in FIG. 8(a), if the film RFhas a tensile stress St, a compressive stress acts on the surface of thesubstrate SUB, and the surface of the substrate SUB deforms (warps) soas to form a concave surface. In contrast, as shown in FIG. 8(b), if thefilm RF has a compressive stress Sc, a tensile stress acts on thesurface of the substrate SUB, and the surface of the substrate SUBdeforms so as to form a convex surface.

Since the resin layer 10 formed by the method described above has atensile stress, the support substrate 60 deforms so as to form a concavesurface as shown in FIG. 8(a), and the edge portion of the supportsubstrate 60 may rise off the horizontal surface. Note that depending onthe material and thickness of the support substrate 60, the supportsubstrate 60 may not warp even if a compressive stress is appliedthereto from the resin layer 10.

Then, as shown in FIGS. 4(a) and 4(b), the adhesive layer 50 is formedon a portion of the resin layer 10. The adhesive layer 50 has openings55 corresponding to the first openings 25 of the magnetic metal body 20to be described below. The adhesive layer 50 may be formed across theentirety of, or a portion of, a region of the resin layer 10 thatcorresponds to the solid portion 21 of the magnetic metal body 20 (theregion to be the second region 10 b). Preferably, it is arranged so asto surround portions of the resin layer 10 that are to be the firstregions 10 a.

The adhesive layer 50 may be a metal layer or may be formed from anadhesive. The adhesive layer 50 may be fixed on the upper surface of theresin layer 10. For example, a metal layer may be formed, as theadhesive layer 50, by a method such as electrolytic plating andelectroless plating. Any of various metal materials may be used as thematerial of the metal layer, which may preferably be Ni, Cu or Sn, forexample. The thickness of the metal layer may be such that it canwithstand the welding step in which it is welded to the magnetic metalbody 20 to be described below, and it may be 1 μm or more and 100 μm orless, for example.

Then, as shown in FIGS. 5(a) and 5(b), the resin layer 10 formed on thesupport substrate 60 is secured on the magnetic metal body 20 so as tocover the first openings 25. The resin layer 10 and the magnetic metalbody 20 are attached together with the adhesive layer 50 therebetween. Aregion 10 a of the resin layer 10 that is located in the first opening25 of the magnetic metal body 20 is the first region, and a region 10 bthat overlaps the solid portion 21 is the second region.

The magnetic metal body 20 is formed from a magnetic metal material, andincludes at least one first opening 25. There is no particularlimitation on the method for manufacturing the magnetic metal body 20.For example, it can be manufactured by providing a magnetic metal plate,and forming the first openings 25 in the magnetic metal plate by aphotolithography process. For example, an invar (an Fe-Ni-based alloyincluding about 36 wt % of Ni) can be preferably used as the material ofthe magnetic metal body 20.

When the adhesive layer 50 is a metal layer, the adhesive layer 50 canbe welded to the magnetic metal body 20 by irradiating the adhesivelayer 50 with a laser beam from the resin layer 10 side. In thisprocess, spot welding may be performed at a plurality of positionsspaced apart from each other by an interval. The number of positions ofspot welding and the interval (pitch) therebetween can be appropriatelyselected. Thus, the resin layer 10 is attached to the magnetic metalbody 20 with the adhesive layer 50 therebetween.

Note that the adhesive layer 50 does not need to be a metal layer. Theresin layer 10 and the magnetic metal body 20 may be attached togetherby using the adhesive layer formed from an adhesive (a dry laminate or aheat laminate).

The adhesive layer 50 may be arranged only in the peripheral edgeportion of the resin layer 10. Where a portion of the magnetic metalbody 20 that overlaps the frame to be provided later is denoted as the“peripheral portion” and a portion thereof that is located in theopening of the frame as the “mask portion”, the adhesive layer 50 may bearranged only between the peripheral portion of the magnetic metal body20 and the resin layer 10. In such a case, in the mask portion, thesolid portion 21 of the magnetic metal body 20 and the resin layer 10are not bonded together.

It is preferred that the adhesive layer 50 is not formed on a portion ofthe resin layer 10 that is to be the first region 10 a. If the adhesivelayer 50 is formed in the first region 10 a, the tensile stress of theresin layer 10 may possibly have an in-plane distribution across thefirst region 10 a even after the support substrate 60 is removed fromthe resin layer 10 in a subsequent step.

Next, as shown in FIGS. 6(a) and 6(b), a plurality of second openings 13are formed in the first region 10 a of the resin layer 10 by a laserablation method, for example, (the laser process step). Thus, the maskmember 30 including the magnetic metal body 20 and the resin layer 10 isobtained.

A pulse laser is used for the laser process on the resin layer 10.Herein, a YAG laser is used, and a predetermined region of the resinlayer 10 is irradiated with a laser beam L1 having a wavelength of 355nm (the third harmonic). The energy density of the laser beam L1 is setto 0.36 J/cm², for example. As described above, the laser process on theresin layer 10 is performed in a plurality of shots while focusing thelaser beam L1 on the surface of the resin layer 10. The shot frequencyis set to 60 Hz, for example. Note that the conditions of the laserprocess (the wavelength of the laser beam, the irradiation conditions,etc.) are not limited to those described above, but can be selectedappropriately so that the resin layer 10 can be processed.

Note that if the resin layer 10 has a stress distribution as describedabove, when the stress distribution in the first region 10 a is leveledafter the support substrate 60 is removed, the size and shape of thesecond openings 13 may change depending on the positions in the firstregion 10 a. In such a case, it is preferred that the second openings 13are formed while taking into consideration the amount of deformation ofthe second openings 13 due to the leveling of the stress distribution,so that the second openings 13 have an intended size and shape after thesupport substrate 60 is removed.

In the present embodiment, a laser process is performed on the resinlayer 10 formed by curing (or baking) on the support substrate 60. Sinceno bubble exists between the support substrate 60 and the resin layer10, it is possible to form the second openings 13 of an intended sizewith a higher precision as compared with conventional methods, and theoccurrence of burrs (see FIG. 27) is also suppressed.

Then, as shown in FIGS. 7(a) and 7(b), the mask member 30 is removedfrom the support substrate 60. The removing of the support substrate 60can be done by a laser lift off method, for example. When the adhesionforce between the resin layer 10 and the support substrate 60 isrelatively weak, the removing can be done mechanically by using a knifeedge, or the like.

Herein, the resin layer 10 is removed from the support substrate 60 byirradiating with a laser beam (wavelength: 308 nm) from the supportsubstrate 60 side by using an XeCl excimer laser, for example. Note thatit is only required that the laser beam be light of a wavelength thatpasses through the support substrate 60 and is absorbed by the resinlayer 10, and a high power laser such as another excimer laser or a YAGlaser may be used.

When the support substrate 60 is removed, the resin layer 10 is kept(tightly) under tension with no slack because of the internal tensilestress. The magnitude of tensile stress in a predetermined direction canbe leveled within portions of the resin layer 10 that are not attachedto the magnetic metal body 20 (herein, the first regions 10 a).

Thereafter, although not shown in the figure, the frame 40 is secured onthe mask member 30 (the frame attachment step). The vapor depositionmask 100 shown in FIG. 1 is manufactured as described above.

In the frame attachment step, the frame 40 is placed on the peripheralportion of the magnetic metal body 20, and the peripheral portion of themagnetic metal body 20 and the frame 40 are attached together. The frame40 is formed from a magnetic metal such as an invar, for example. Theperipheral portion of the magnetic metal body 20 and the frame 40 may bewelded together by irradiating with a laser beam from the resin layer 10side (spot welding). The pitch of the spot welding can be selectedappropriately. Note that in the example shown in FIG. 1, the inner edgeportion of the frame 40 and the inner edge portion of the magnetic metalbody 20 are generally aligned together as seen from a direction normalto the support substrate 60, but a portion of the magnetic metal body 20may be exposed on the inner side of the frame 40. Alternatively, theframe 40 may cover the entire peripheral portion of the magnetic metalbody 20 and a portion of the resin layer 10.

As described above, in the present embodiment, the step of securing theresin layer 10 and the magnetic metal body 20 on the frame 40 whilestretching them in a predetermined layer in-plane direction (thestretching step) is not performed, it is possible to use the frame 40having a lower rigidity as compared with conventional methods.Therefore, the frame 40 may be formed from a resin such as ABS(acrylonitrile butadiene styrene) and PEEK (polyether ether ketone). Themethod for attaching together the mask member 30 and the frame 40 is notlimited to laser welding. For example, the peripheral portion of themagnetic metal body 20 and the frame 40 may be attached together byusing an adhesive, for example.

Thereafter, as necessary, a magnetization step of magnetizing themagnetic metal body 20 with an electromagnetic coil is performed,adjusting the residual magnetic flux density of the magnetic metal body20 to 10 mT or more and 1000 mT, for example. Note that themagnetization step does not need to be performed. Even if themagnetization step is not performed, the magnetic metal body 20 is amagnetic member, and the vapor deposition mask 100 can be held on thework in the vapor deposition step by using a magnetic chuck.

While a method for forming the vapor deposition mask 100 has beendescribed above as an example, the other vapor deposition masks 200 and300 can also be manufactured by a method similar to the method describedabove.

<Another Method for Manufacturing Vapor Deposition Mask>

With the method described above with reference to FIG. 3 to FIG. 7, thesecond openings 13 are formed in the resin layer 10 after the resinlayer 10 and the magnetic metal body 20 are attached together, but thesecond openings 13 may be formed before the resin layer 10 and themagnetic metal body 20 are attached together. With the method describedabove with reference to FIG. 3 to FIG. 7, the support substrate 60 isremoved from the mask member 30 before the mask member 30 and the frame40 are attached together, but the support substrate 60 may be removedafter the frame 40 and the mask member 30 are attached together.Moreover, before the resin layer 10 and the magnetic metal body 20 areattached together, the frame 40 may be attached to the magnetic metalbody 20.

Another method for manufacturing a vapor deposition mask of the presentembodiment will now be described with reference to the drawings. In thefigures, like components to those of FIG. 3 to FIG. 7 are denoted bylike reference signs. The description will focus on differences from themethod described above with reference to FIG. 3 to FIG. 7, and themethod of formation, material, thickness, etc., of the layers will notbe described below if they are similar to those of the method describedabove.

FIGS. 9(a) to 9(e) are cross-sectional views each showing a step ofanother method for manufacturing a vapor deposition mask.

First, as shown in FIG. 9(a), the resin layer 10 is formed on thesupport substrate 60. The method for forming the resin layer 10 issimilar to the method described above with reference to FIG. 3. Herein,the resin layer 10 is formed by applying and curing a polyimide varnishon the support substrate 60.

Then, as shown in FIG. 9(b), the second openings 13 are formed in theresin layer 10 by a laser process. The second openings 13 are formed ina region of the resin layer that is located within the first opening 25of the magnetic metal body 20 when the resin layer 10 is attached to themagnetic metal body 20 in a subsequent step.

Then, as shown in FIG. 9(c), the resin layer 10 and the magnetic metalbody 20 are attached together with the adhesive layer 50 therebetween.The attachment method is similar to the method described above withreference to FIG. 5.

Thereafter, as shown in FIG. 9(d), the support substrate 60 is removedfrom the resin layer 10 by a laser lift off method, for example.

Then, as shown in FIG. 9(e), the frame 40 is provided on the peripheralportion of the magnetic metal body 20 by performing spot welding using alaser beam L2, for example. Thus, the vapor deposition mask 100 isobtained.

FIGS. 10(a) to 10(e) are cross-sectional views each showing a step ofanother method for manufacturing a vapor deposition mask.

First, as shown in FIG. 10(a), the resin layer 10 is formed on thesupport substrate 60. The method for forming the resin layer 10 issimilar to the method described above with reference to FIG. 3.

Then, as shown in FIG. 10(b), the resin layer 10 and the magnetic metalbody 20 are attached together with the adhesive layer 50 therebetween.

Then, as shown in FIG. 10(c), the second openings 13 are formed in theresin layer 10 by a laser process.

Thereafter, as shown in FIG. 10(d), the frame 40 is provided on theperipheral portion of the magnetic metal body 20 by performing spotwelding using the laser beam L2, for example.

Then, as shown in FIG. 10(e), the support substrate 60 is remover fromthe resin layer 10 by a laser lift off method, for example. Thus, thevapor deposition mask 100 is obtained.

FIGS. 11(a) to 11(e) are cross-sectional views each showing a step ofstill another method for manufacturing a vapor deposition mask.

First, as shown in FIG. 11(a), the resin layer 10 is formed on thesupport substrate 60. The method for forming the resin layer 10 issimilar to the method described above with reference to FIG. 3.

As shown in FIG. 11(b), the magnetic metal body 20 is attached to theframe 40, thereby forming a frame structure. Specifically, the frame 40is placed on the peripheral portion of the magnetic metal body 20, andthe peripheral portion and the frame 40 are attached together. Herein,the peripheral portion of the magnetic metal body 20 and the frame 40are welded together by irradiating from the magnetic metal body 20 sidewith a laser beam L3. For example, spot welding may be performed at aplurality of positions with a predetermined interval therebetween. Notethat the magnetic metal body 20 may be attached to the frame with aconstant tension acting in a predetermined direction on the magneticmetal body 20 by using a stretch welding machine. Note however that inthe present embodiment, there is no need to apply a high tension becauseit is only required that the magnetic metal body 20 be secured on theframe 40.

Then, as shown in FIG. 11(c), the resin layer 10 and the magnetic metalbody 20 are attached together with the adhesive layer 50 therebetween.

Then, as shown in FIG. 11(d), the second openings 13 are formed in theresin layer 10 by a laser process.

Thereafter, as shown in FIG. 11(e), the support substrate 60 is removedfrom the resin layer 10 by a laser lift off method, for example. Thus,the vapor deposition mask 100 is obtained.

Thus, the vapor deposition mask 100 of the present embodiment can bemanufactured by various methods. Note that with the method shown in FIG.9, it is necessary to perform a high-precision alignment when the resinlayer 10 with the second openings 13 formed therein is attached to themagnetic metal body 20. In contrast, if the second openings 13 areformed after the resin layer 10 and the magnetic metal body 20 areattached together, there is advantageously no need to perform such ahigh-precision alignment.

With the method shown in FIG. 10 and FIG. 11, the frame 40 is attachedbefore the support substrate 60 is removed. In such a case, the supportsubstrate 60 is removed by placing the support substrate 60, with theheavy and bulky frame 40 attached thereto, on the stage of a laserlift-off device. Therefore, as compared with other methods, it isnecessary that the stage of the laser lift-off device to be used belarge and strong. Moreover, the distance WD between the laser head andthe stage (the work distance) needs to be large. In contrast, performingthe attachment step of the frame 40 after the support substrate 60 isremoved is more practical because there will not be such limitations asdescribed above on the size, strength and WD for the stage of the laserlift-off device.

Advantageous Effects of Manufacturing Method of Present Embodiment

With the method for manufacturing a vapor deposition mask of the presentembodiment, the resin layer 10 is formed by applying a solutionincluding a resin material or a solution including a precursor of aresin material on the surface of the support substrate 60, andperforming a heat treatment. The resin layer 10 formed by this method isin close contact with the support substrate 60, and no bubble occurs atthe interface between the resin layer 10 and the support substrate 60.Therefore, by forming a plurality of second openings 13 in the resinlayer 10 on the support substrate 60, it is possible to form secondopenings 13 of an intended size with a higher precision as compared withconventional methods, and it is also possible to suppress the occurrenceof the burrs 98 (see FIG. 27).

According to the present embodiment, an intended tensile stress can becaused on the resin layer 10. Thus, it is possible to reduce the bendamount in the first region 10 a of the resin layer 10. Therefore, theresin layer 10 can be kept in close contact on the vapor depositionsubstrate without arranging a magnetic metal close to the secondopenings 13 of the first region 10 a. Therefore, it is possible toincrease the size of the first opening 25, and it is possible to allowthe use of an open mask, for example. It is also possible to use themagnetic metal body 20 of which the area ratio of the solid portion isvery small (e.g., 50% or less with respect to the area of the maskportion). Moreover, there is no need to form a magnetic metal layer thatis patterned with a high precision, and it is therefore possible tosimplify the manufacturing step. Furthermore, it is also possible to usea metal material having a large thermal expansion coefficient αM.Therefore, the degree of freedom in selecting the shape and the metalmaterial of the magnetic metal body 20 can be increased as compared withconventional methods.

In the present embodiment, the resin layer 10 is formed on the supportsubstrate 60, and the resin layer 10 being supported on the supportsubstrate 60 is attached to the magnetic metal body 20. Since the resinlayer 10 has a predetermined tensile stress as a residual stress, thestretching step of attaching the resin layer 10 to the frame whilestretching the resin layer 10 is not performed. Since there is no needto perform the stretching step using a large-scale stretcher, it ispossible to reduce the manufacturing cost. Since the stretching step isnot performed, tension in a predetermined layer plane direction(s) isnot applied to the magnetic metal body 20 from the frame 40. Therefore,the rigidity of the frame 40 can be made smaller as compared withconventional methods, thereby increasing the degree of freedom inselecting the material of the frame 40 and the degree of freedom indesigning the width, the thickness, etc., of the frame.

With conventional methods described in Patent Document No. 1, etc., alaser process for the resin film is performed after the resin film issecured to the frame by the stretching step. In contrast, according tothe present embodiment, the attachment step of the frame 40 may beperformed before the laser process on the resin layer 10 or after thelaser process. There are advantages as follows when the attachment stepof the frame 40 is performed after the laser process. The mask member 30supported on the support substrate 60 before the frame 40 is attachedthereto (including the mask member before the laser process) is lighterand easier to handle than the mask member 30 after the frame 40 isattached thereto, thereby facilitating operations such as placing it onthe laser process machine and carrying it around. Since the frame 40 isnot attached thereto, it is easy to irradiate the resin layer 10 withthe laser beam L1 and it is easy to process the resin layer 10.Moreover, with the method of Patent Document No. 1, when the laserprocess of the resin layer is not successful, there is a need to removethe layered mask off the frame. However, if the laser process isperformed before the frame 40 is attached, there is no need for such aremoving step.

Moreover, a resin film that has been secured to the frame by thestretching step is sensitive to changes in surrounding environments suchas humidity and temperature, and the bend amount of the resin film mayvary depending on the surrounding environments. In contrast, in thepresent embodiment, the bend of the resin layer 10 is zero or verysmall, and the bend amount does not substantially change over time.

The magnitude of temperature increase of the vapor deposition maskduring the vapor deposition step, i.e., the difference ΔT (° C.)(=T2−T1) between temperature T1 of the vapor deposition mask during themanufacturing process and temperature T2 of the vapor deposition maskduring the vapor deposition step varies depending on the vapordeposition method, the vapor deposition device, etc. When thetemperature difference ΔT is suppressed to be relatively small, ΔT isless than 3° C., i.e., about 1° C. On the other hand, ΔT may be about 3°C. to about 15° C. Note that temperature T1 during the manufacturingprocess of the present embodiment is the temperature of the environmentin which the manufacturing device (e.g., the laser process machine usedfor processing the resin layer 10, the welder used in the frameattachment step, etc.) is installed, e.g., room temperature. When vapordeposition is performed while relatively moving (scanning) the positionof the vapor deposition source with respect to the work, temperature T2during the vapor deposition step refers to the temperature of theportion of the vapor deposition mask where vapor deposition is beingperformed. In the present embodiment, when ΔT is relatively large (e.g.,over 3° C.), it is possible to suppress the positional misalignment bythe following method, as necessary. First, the temperature increase (ΔT)of the vapor deposition mask is measured in advance. Then, based on themeasurement result of ΔT, the amount of positional misalignmentoccurring due to thermal expansion is calculated. The amount ofpositional misalignment includes the misalignment between the positionof the second opening 13 and the vapor deposition position, and themisalignment between the shape of the second opening 13 and the intendedvapor deposition pattern caused by the deformation of the second opening13 itself. The size of the second opening 13 of the resin layer 10 isformed to be smaller than the intended vapor deposition pattern by apredetermined amount so as to cancel out the amount of positionalmisalignment. Note that instead of calculating the amount of positionalmisalignment, the amount of positional misalignment may be measuredthrough an actual vapor deposition process.

(Relationship Between Heat Treatment Condition and Tensile Stress ofResin Layer)

The present inventors studied the relationship of the resin layerformation conditions (heat treatment conditions) with the tensile stressof the resin layer and the bend amount of the resin layer. The methodand results of the study will now be described.

Method for Producing Samples A to C

A polyimide film 62 was formed on a glass substrate 61 while varying theheat treatment conditions, thereby obtaining Samples A to C. FIG. 12 isa top view of Samples A to C.

First, the glass substrate (AN-100 from Asahi Glass Co., Ltd.) 61 wasprovided as the support substrate. The thermal expansion coefficient ofthe glass substrate 61 was 3.8 ppm/° C., the size thereof was 370 mm×470mm, and the thickness thereof was 0.5 mm.

A polyimide varnish (U-Varnish-S from Ube Industries, Ltd.) was appliedon a portion of the glass substrate 61 described above. Herein, thepolyimide varnish was applied over a predetermined area (330 mm×366 mm)of the glass substrate 61 as shown in FIG. 12.

Then, a heat treatment was performed under a vacuum atmosphere(pressure: 20 Pa) on the glass substrate 61 with a polyimide varnishapplied thereon, thereby forming the polyimide film 62. In the heattreatment, the temperature was increased from room temperature (herein,25° C.) to 500° C. (highest temperature), and the temperature was heldat 500° C. for a predetermined amount of time. Thereafter, a nitrogengas was supplied as a purge gas, followed by rapid cooling (3 min).Table 1 shows the heating time up to 500° C., the hold time at 500° C.,the heating speed (from room temperature to when 500° C. was reached)and the thickness of the polyimide film 62 for each sample.

Thus, the glass substrates 61 with the polyimide film 62 formed thereonwere obtained as Samples A to C. With Samples A to C, the tensile stressof the polyimide film 62 gave a compressive stress on the glasssubstrate 61, thereby warping the glass substrate 61. Table 1 shows theaverage value of the warp amount of the glass substrate 61 in thelongitudinal direction and that in the width direction.

Calculation of Tensile Stress of Polyimide Film 62

Then, the tensile stress of the polyimide film 62 was calculated basedon the warp amount of the glass substrate 61 for Samples A to C. Theresults are shown in Table 1. The tensile stress can be obtained fromthe thickness, the Young's modulus and the Poisson's ratio of the glasssubstrate 61, the thickness of the polyimide film 62, and the radius ofcurvature (approximate value) of the warp of the glass substrate 61, byusing the Stoney's formula.

Table 1 also shows the results obtained when a polyimide film wasproduced under a low heating speed condition for reference (denoted as“Sample D”). As shown in Table 1, Sample D was heated in a stepwisemanner up to 450° C. by holding the temperature for a predeterminedamount of time after reaching 120° C., 150° C. and 180° C. The tensilestress of Sample D was a value calculated assuming that the warp of theglass substrate 61 was 10 μm.

TABLE 1 Sample A Sample B Sample C Sample D Heat Temperature Room tempto 500° C. Room temp to treatment 450° C. conditions Pressure 20 PaAtmospheric pressure Heating time 8 min 13 min 21 min 195 min (heat for(heat for (heat for (holding at 3 min, 8 min, 16 min, 120° C. for holdfor hold for hold for 10 min, 5 min) 5 min) 5 min) holding at 150° C.for 10 min, holding at 180° C. for 60 min, holding at 450° C. for 30min) Heating 158° C./min 59° C./min 30° C./min 5° C./min speed Thicknessof polyimide 10 20 20 20 film (pm) Warp amount of glass 23 620 230 10 orless substrate in longitudinal direction (μm) Warp amount of glass 6 400130 10 or less substrate in width direction (μm) Tensile stress on 0.29.6 3.3 0.2 polyimide film (MPa)

Moreover, six samples B1 to B6 were produced using the same heattreatment conditions, and the tensile stress on the polyimide film 62was calculated. The heat treatment conditions for Samples B1 to B6 weresimilar to those for Sample B (room temperature to 500° C., pressure: 20Pa, heating time: 13 min (heating for 8 min+holding for 5 min), heatingspeed: 59° C./min). Note however that the speed of depressurizing thechamber in which the glass substrate 61 with a polyimide varnish appliedthereon was placed before the heat treatment was set to be lower thanthat for Sample B. Also for these samples, the tensile stress on thepolyimide film was obtained from the warp amount of the glass substrateas described above. The results are shown in Table 2.

TABLE 2 B1 B2 B3 B4 B5 B6 Thickness of polyimide 20 film (μm) Warpamount of glass 750 700 710 680 690 670 substrate in longitudinaldirection (μm) Warp amount of glass 500 500 520 470 500 540 substrate inwidth direction (μm) Tensile stress on 11.7 11.4 11.7 10.8 11.2 11.4polyimide film (MPa)

From the results above, it was confirmed that it is possible to controlthe tensile stress on the resin layer on the support substrate based onthe heat treatment conditions. For example, it was found that it ispossible to form a resin layer of a large tensile stress by increasingthe heating speed. Note that although the heat treatment was performedwhile varying the heating speed for each sample, it is possible to varythe magnitude of tensile stress on the resin layer also by varying theheat treatment conditions other than the heating speed.

EXAMPLES

Examples of vapor deposition masks were produced, and the bend amount ofthe resin layer was evaluated therefor, the results of which will now bedescribed.

FIG. 13(a) is a plan view showing a vapor deposition mask of Example 1,and FIG. 13(b) is a cross-sectional view taken along line B-B of FIG.13(a). The method for producing the vapor deposition mask of Example 1was similar to the method described above with reference to FIG. 11.

Production of Vapor Deposition Mask of Example 1

In Example 1, a glass substrate (200×130 mm, thickness: 0.5 mm) was usedas the support substrate. A polyimide film (thickness: 20 μm) 71 wasformed on the glass substrate under similar heat treatment conditions tothose for Sample B described above.

An open mask (200×110 mm, thickness: 100 μm) 72 having three firstopenings (50 mm×90 mm) 73 was provided as the magnetic metal body. Theopen mask 72 was welded to an SUS frame (200×130 mm, thickness: 10 mm,frame width: 20 mm) (not shown).

Then, an epoxy resin adhesive (EP330 from Cemedine Co., Ltd.) 75 wasapplied, as the adhesive layer, on a portion of the polyimide film 71 onthe glass substrate. Thereafter, the polyimide film 71 and the open mask72 were attached to each other with the adhesive 75 therebetween.

Then, the support substrate was removed from the polyimide film 71. Nosecond openings were provided in the polyimide film 71. Thus, the vapordeposition mask of Example 1 was obtained.

The vapor deposition mask of Example 1 includes three cells C1 to C3.Herein, “cell” refers to a first opening 73 and an area therearound, asthe vapor deposition mask is seen from a normal direction, andcorresponds to the unit region U described above. In each cell, a region71 a of the polyimide film 71 that is exposed through the first opening73 is referred to as the “first region”, and a region 71 b attached tothe open mask 72 by the adhesive 75 is referred to as the “secondregion”.

Production of Vapor Deposition Mask of Example 2

The vapor deposition mask of Example 2 was produced by a method similarto Example 1 except that the polyimide film 71 was formed under similarheat treatment conditions to those for Sample D described above. Notehowever that in Example 2, the polyimide film 71 was not applied to oneof the three first openings 73 of the open mask 72 that was located atthe center. Thus, the vapor deposition mask of Example 2 includes twocells.

Observation of Vapor Deposition Masks of Examples 1 and 2

Photographs of the vapor deposition masks of Example 1 and Example 2 areshown in FIGS. 23(a) and 23(b). With the vapor deposition mask ofExample 1, there are no creases dependent on the bend of the polyimidefilm 71. The polyimide film 71 is observed to have a pattern that seemsto be dependent on the film stress distribution. On the other hand, withthe vapor deposition mask of Example 2, there are creases dependent onthe bend of the polyimide film 71, and it can be seen that the bend islarge in the central portion of the cell.

Bend Measurement of Polyimide Film 71

The bend of the polyimide film 71 was measured for each of the cells C1to C3 of the vapor deposition mask of Example 1.

FIGS. 14(a) and 14(b) are plan views each showing the scan direction ofeach cell in the bend measurement. The change in the height of thepolyimide film 71 was examined by scanning the first opening 73 of eachcell in the width direction and in the longitudinal direction by using alaser displacement meter (LK-H057K from Keyence Corporation). The datasampling frequency was set to 200 μs.

FIG. 15 to FIG. 20 are graphs showing the measurement results of thepolyimide film 71 of each cell in the vapor deposition mask of Example1.

FIGS. 15(a) to 15(c) and FIGS. 16(a) to 16(c) are graphs each showingthe change in the height of the polyimide film 71 of the cell C1 in thevapor deposition mask of Example 1. Similarly, FIGS. 17(a) to 17(c) andFIGS. 18(a) to 18(c) are graphs each showing the change in the height ofthe polyimide film 71 of the cell C2, and FIGS. 19(a) to 19(c) and FIGS.20(a) to 20(c) are graphs each showing the change in the height of thepolyimide film 71 of the cell C3. In FIG. 15, FIG. 17 and FIG. 19, (a)to (c) show the measurement results obtained by scanning the polyimidefilm 71 in the width direction of the cell along lines I-I, II-II andIII-III, respectively, of FIG. 14(a). In FIG. 16, FIG. and FIG. 20, (a)to (c) show the measurement results obtained by scanning the polyimidefilm 71 in the longitudinal direction of the cell along lines of IV-IV,V-V and VI-VI, respectively, of FIG. 14(a).

In these figures, the vertical axis represents the height of thepolyimide film 71, which is the value obtained with respect to theheight of the central portion of each cell. The horizontal axisrepresents the number of data points obtained at an interval of 200 μs.Note that since the sensor is moved manually for the measurement and thescanning speed of the sensor is not constant, the horizontal axis doesnot correspond to the distance.

In FIG. 15 to FIG. 20, the height of the first region 71 a of thepolyimide film 71 has a gradient, which is dependent on the tilt of theframe, the thickness variations of the adhesive 75, etc. There is a steph between the first region 71 a and the second region 71 b of thepolyimide film 71. This is because the vapor deposition mask of Example1 is placed with the polyimide film 71 facing up, and the measurement isperformed by the displacement meter from below (from the side of theopen mask 72 of the polyimide film 71). The step h corresponds to thetotal thickness of the open mask 72 and the adhesive 75.

A broken line represents the correction line on the measurement resultsalong the cross sections of the cells C1 to C3. The “correction line”represents the change in the height of the polyimide film 71 (the firstregion 71 a) when the bend of the polyimide film 71 is zero. When thepolyimide film 71 has a bend, the actual measurement of the height ofthe polyimide film 71 is smaller than the height of the correction line.Herein, the maximum value of the height difference between thecorrection line and the actual measurement (where the actual measurementis a negative value with respect to the height of the correction line)was obtained as the bend amount of the polyimide film 71 along eachcross section. The maximum value of the bend amount was used as the“maximum bend amount” of the cell.

As a result, the maximum bend amount was 5 μm or less for any cell.Therefore, it was found that for the vapor deposition mask of Example 1,the first region 71 a of the polyimide film 71 has a predeterminedtensile stress, irrespective of the position of the cell, and the bendamount (i.e., the height difference between the actual measurement andthe correction line) can be suppressed. It was also found that thestress distribution occurring immediately after the heat treatment isdecreased (leveled) in the first region 71 a of the polyimide film 71.

On the other hand, also for the cell of the vapor deposition mask ofExample 2, the bend measurement of the polyimide film 71 was performedto obtain the maximum bend amount by a similar method to that of Example1.

FIGS. 21(a) to 21(c) and FIGS. 22(a) to 22(c) each show the change inthe height of the polyimide film 71 of one cell of the vapor depositionmask of Example 2, showing the measurement results obtained by scanningthe polyimide film 71 along lines I-I, II-II, III-III, IV-IV, V-V andVI-VI of FIGS. 14 (a) and 14(b).

As a result, it was found that with the vapor deposition mask of Example2, the maximum bend amount was 400 μm or more and 500 μm or less foreach cell, indicating that there was a greater bend than with Example 1.Thus, it was confirmed that it is possible to reduce the bend amount ofthe polyimide film 71 by increasing the tensile stress of the polyimidefilm 71.

Note that a resin film having a predetermined tensile stress (e.g., 3MPa or more) and a conventional resin film formed under conditions suchthat the tensile stress will be relatively small can be distinguishedfrom each other by, for example, measuring the compressive stress (warpamount) on the support substrate or the magnetic metal body, ormeasuring the in-plane orientation (IR absorption spectrum) of the resinfilm. For example, while the IR absorption spectrum is substantially thesame for the front surface and for the reverse surface with aconventional resin film, there may occur differences such as adifference in the IR absorption spectrum between the front surface andthe reverse surface for a resin film having a large tensile stress. Aresin film having a predetermined tensile stress that is attached to anopen mask and a conventional resin film secured on a frame while beingstretched can also be distinguished from each other by observation usingpolarized light, for example.

(Method for Manufacturing Organic Semiconductor Device)

A vapor deposition mask according to an embodiment of the presentinvention can suitably be used in the vapor deposition step in a methodfor manufacturing an organic semiconductor device.

The following description is directed to, as an example, a method formanufacturing an organic EL display device.

FIG. 24 is a cross-sectional view schematically showing an organic ELdisplay device 500 of a top emission type.

As can be seen from FIG. 24, the organic EL display device 500 includesan active matrix substrate (TFT substrate) 510 and an encapsulationsubstrate 520, and includes a red pixel Pr, a green pixel Pg and a bluepixel Pb.

The TFT substrate 510 includes an insulative substrate, and a TFTcircuit formed on the insulative substrate (neither is shown in thefigure). A flattening film 511 is provided so as to cover the TFTcircuit. The flattening film 511 is formed from an organic insulativematerial.

Lower electrodes 512R, 512G and 512B are provided on the flattening film511. The lower electrodes 512R, 512G and 512B are formed in the redpixel Pr, the green pixel Pg and the blue pixel Pb, respectively. Thelower electrodes 512R, 512G and 512B are each connected to the TFTcircuit, and function as an anode. A bank 513 covering the edge portionof the lower electrodes 512R, 512G and 512B is provided between adjacentpixels. The bank 513 is formed from an insulative material.

Organic EL layers 514R, 514G and 514B are provided on the lowerelectrodes 512R, 512G and 512B of the red pixel Pr, the green pixel Pgand the blue pixel Pb, respectively. The organic EL layers 514R, 514Gand 514B each have a layered structure including a plurality of layersformed from an organic semiconductor material. For example, the layeredstructure includes a hole injection layer, a hole transport layer, alight emitting layer, an electron transport layer and an electroninjection layer that are arranged in this order from the side of thelower electrodes 512R, 512G and 512B. The organic EL layer 514R of thered pixel Pr includes a light emitting layer that emits red light. Theorganic EL layer 514G of the green pixel Pg includes a light emittinglayer that emits green light. The organic EL layer 514B of the bluepixel Pb includes a light emitting layer that emits blue light.

An upper electrode 515 is provided on the organic EL layers 514R, 514Gand 514B. The upper electrode 515 is formed, by using a transparentconductive material, so as to be continuous over the entire display area(i.e., as a shared member among the red pixel Pr, the green pixel Pg andthe blue pixel Pb), and functions as a cathode. A protection layer 516is provided on the upper electrode 515. The protection layer 516 isformed from an organic insulative material.

The structure of the TFT substrate 510 described above is encapsulatedby the encapsulation substrate 520, which is bonded to the TFT substrate510 via a transparent resin layer 517.

The organic EL display device 500 can be produced as follows by using avapor deposition mask according to an embodiment of the presentinvention. FIGS. 25(a) to 25(d) and FIGS. 26(a) to 26(d) arecross-sectional views each showing a step in the process ofmanufacturing the organic EL display device 500. Note that the followingdescription will focus on the step of vapor-depositing an organicsemiconductor material on the work (forming the organic EL layers 514R,514G and 514B on the TFT substrate 510) by using a vapor deposition mask101R for red pixels, a vapor deposition mask 101G for green pixels and avapor deposition mask 101B for blue pixels in turns.

First, as shown in FIG. 25(a), the TFT substrate 510 is provided,wherein the TFT substrate 510 includes the TFT circuit, the flatteningfilm 511, the lower electrodes 512R, 512G and 512B and the bank 513formed on an insulative substrate. The steps of forming the TFT circuit,the flattening film 511, the lower electrodes 512R, 512G and 512B andthe bank 513 can be carried out by any of various methods known in theart.

Next, as shown in FIG. 25(b), a carrier device is used to arrange theTFT substrate 510 close to the vapor deposition mask 101R, which is heldin the vacuum vapor deposition device. In this process, the vapordeposition mask 101R and the TFT substrate 510 are positioned so thatthe second opening 13R of the resin layer 10 overlaps the lowerelectrode 512R of the red pixel Pr. A magnetic chuck (not shown)arranged on the opposite side from the vapor deposition mask 101R withrespect to the TFT substrate 510 is used to hold the vapor depositionmask 101R in close contact with the TFT substrate 510.

Then, as shown in FIG. 25(c), organic semiconductor materials aresuccessively deposited on the lower electrode 512R of the red pixel Prby vacuum vapor deposition, thereby forming the organic EL layer 514Rincluding a light emitting layer that emits red light.

Next, as shown in FIG. 25(d), the vapor deposition mask 101G is placedin the vacuum vapor deposition device, replacing the vapor depositionmask 101R. The vapor deposition mask 101G and the TFT substrate 510 arepositioned together so that the second opening 13G of the resin layer 10overlaps the lower electrode 512G of the green pixel Pg. A magneticchuck is used to hold the vapor deposition mask 101G in close contactwith the TFT substrate 510.

Then, as shown in FIG. 26(a), organic semiconductor materials aresuccessively deposited on the lower electrode 512G of the green pixel Pgby vacuum vapor deposition, thereby forming the organic EL layer 514Gincluding a light emitting layer that emits green light.

Next, as shown in FIG. 26(b), the vapor deposition mask 101B is placedin the vacuum vapor deposition device, replacing the vapor depositionmask 101G. The vapor deposition mask 101B and the TFT substrate 510 arepositioned together so that the second opening 13B of the resin layer 10overlaps the lower electrode 512B of the blue pixel Pb. A magnetic chuckis used to hold the vapor deposition mask 101B in close contact with theTFT substrate 510.

Then, as shown in FIG. 26(c), organic semiconductor materials aresuccessively deposited on the lower electrode 512B of the blue pixel Pbby vacuum vapor deposition, thereby forming the organic EL layer 514Bincluding a light emitting layer that emits blue light.

Next, as shown in FIG. 26(d), the upper electrode 515 and the protectionlayer 516 are formed successively on the organic EL layers 514R, 514Gand 514B. The formation of the upper electrode 515 and the protectionlayer 516 can be carried out by any of various methods known in the art.Thus, the TFT substrate 510 is obtained.

Then, the encapsulation substrate 520 is bonded to the TFT substrate 510via the transparent resin layer 517, thereby completing the organic ELdisplay device 500 shown in FIG. 24.

Note that although three vapor deposition masks 101R, 101G and 101Bcorresponding respectively to the organic EL layers 514R, 514G and 514Bof the red pixel Pr, the green pixel Pg and the blue pixel Pb are usedherein, the organic EL layers 514R, 514G and 514B correspondingrespectively to the red pixel Pr, the green pixel Pg and the blue pixelPb may be formed by successively shifting a single vapor depositionmask. With the organic EL display device 500, an encapsulation film maybe used instead of the encapsulation substrate 520. Alternatively,instead of using an encapsulation substrate (or an encapsulation film),a thin film encapsulation (TFE) structure may be provided over the TFTsubstrate 510. A thin film encapsulation structure includes a pluralityof inorganic insulating films such as silicon nitride films, forexample. The thin film encapsulation structure may further include anorganic insulative film.

Note that although the organic EL display device 500 of a top emissiontype is illustrated in the above description, it is needless to say thatthe vapor deposition mask of the present embodiment may be used formanufacturing an organic EL display device of a bottom emission type.

An organic EL display device to be manufactured by using the vapordeposition mask of the present embodiment does not necessarily need tobe a rigid device. The vapor deposition mask of the present embodimentcan suitably be used in the manufacture of a flexible organic EL displaydevice. In a method for manufacturing a flexible organic EL displaydevice, a TFT circuit, etc., are formed on a polymer layer (e.g., apolyimide layer) formed on a support substrate (e.g., a glasssubstrate), and the polymer layer, together with the layered structurethereon, is removed from the support substrate (e.g., a laser lift offmethod is used) after the formation of a protection layer.

The vapor deposition mask of the present embodiment may be also used inthe manufacture of an organic semiconductor device other than an organicEL display device, and can particularly suitably be used in themanufacture of an organic semiconductor device for which it is necessaryto form a vapor deposition pattern having a high definition.

INDUSTRIAL APPLICABILITY

The vapor deposition mask according to an embodiment of the presentinvention can suitably be used in the manufacture of an organicsemiconductor device such as an organic EL display device, and canparticularly suitably be used in the manufacture of an organicsemiconductor device for which it is necessary to form a vapordeposition pattern having a high definition.

REFERENCE SIGNS LIST

-   10 Resin layer-   10 a First region-   10 b Second region-   13 Opening-   20 Magnetic metal body-   21 Solid pattern portion-   25 Opening-   30 Mask member-   40 Frame-   50 Adhesive layer-   60 Support substrate-   L1, L1, L3 Laser beam-   100, 200, 300 Vapor deposition mask-   500 Organic EL display device-   510 TFT substrate-   511 Flattening film-   512B, 512G, 512R Lower electrode-   513 Bank-   514B, 514G, 514R Organic EL layer-   515 Upper electrode-   516 Protection layer-   517 Transparent resin layer-   520 Encapsulation substrate-   Pb Blue pixel-   Pg Green pixel-   Pr Red pixel-   U Unit region

1. A method for manufacturing a vapor deposition mask including a resinlayer, and a magnetic metal body formed on the resin layer, the methodcomprising the steps of: (A) providing a magnetic metal body having atleast one first opening; (B) providing a substrate; (C) forming a resinlayer by applying a solution including a resin material or a varnish ofa resin material on a surface of the substrate, and then performing aheat treatment thereon; (D) after the steps (A), (B) and (C), securingthe resin layer formed on the substrate onto the magnetic metal body soas to cover the at least one first opening, the step (D) including (D1)forming a metal layer by plating on a portion of the resin layer, and(D2) attaching the resin layer to the magnetic metal body with the metallayer therebetween; (E) forming a plurality of second openings in theresin layer; and (F) after the steps (D) and (E), removing the substratefrom the resin layer.
 2. The manufacturing method according to claim 1,wherein: the step (E) is performed after the step (D); and the pluralityof second openings are formed in the region of the resin layer that islocated in the at least one first opening of the magnetic metal body. 3.The manufacturing method according to claim 1, wherein the step (E) isperformed between the step (C) and the step (D).
 4. The manufacturingmethod according to claim 1, further comprising the step of providing aframe along a peripheral edge portion of the magnetic metal body.
 5. Themanufacturing method according to claim 1, wherein in the step (C), theheat treatment is performed under such a condition that a tensile stressgreater than 0.2 MPa is produced on the resin layer at room temperaturein a layer in-plane direction.
 6. The manufacturing method according toclaim 1, wherein a compressive stress is applied on the magnetic metalbody from the resin layer after the substrate is removed in the step(F).
 7. The manufacturing method according to claim 1, wherein the step(D2) includes a step of welding the metal layer to the magnetic metalbody, thereby attaching the resin layer to the magnetic metal body withthe metal layer therebetween.
 8. The manufacturing method according toclaim 1, wherein a width in a width direction of the at least one firstopening is 30 mm or more.
 9. The manufacturing method according to claim1, wherein a thickness of the magnetic metal body is 300 μm or more. 10.The manufacturing method according to claim 1, wherein: the vapordeposition mask is a mask used for forming a plurality of devices on avapor deposition substrate, the vapor deposition mask having a pluralityof unit regions each corresponds to one of the plurality of devices, andthe magnetic metal body has an open mask structure in which only onefirst opening is arranged for each one of the plurality of unit regions.11. The manufacturing method according to claim 5, wherein in the step(C), the heat treatment is performed under such a condition that thetensile stress is 3 MPa or more is produced on the resin layer at roomtemperature in a layer in-plane direction.
 12. The manufacturing methodaccording to claim 1, wherein the metal layer is not present on a regionof the resin layer that is located in the at least one first opening ofthe magnetic metal body.
 13. The manufacturing method according to claim1, wherein there is no magnetic metal on a region of the resin layerthat is located in the at least one first opening of the magnetic metalbody.
 14. The manufacturing method according to claim 1, wherein, in thestep (C), the heat treatment is performed at a first temperature, thestep (D) is performed at a second temperature lower than the firsttemperature, and the step (F) is performed at a third temperature lowerthan the first temperature.
 15. A vapor deposition mask comprising: aframe; a magnetic metal body supported on the frame and including atleast one first opening; a resin layer arranged on the magnetic metalbody so as to cover the at least one first opening; and an adhesivelayer located between the resin layer and the magnetic metal body forattaching together the resin layer and the magnetic metal body, wherein:the resin layer has a tensile stress in a layer in-plane direction; andthe magnetic metal body receives a compressive stress in an in-planedirection from the resin layer.
 16. The vapor deposition mask accordingto claim 15, wherein the tensile stress of the resin layer is greaterthan 0.2 MPa at room temperature.
 17. The vapor deposition maskaccording to claim 15, wherein there is no magnetic metal on a region ofthe resin layer that is located in the at least one first opening of themagnetic metal body.
 18. The vapor deposition mask according to claim15, wherein: the adhesive layer is a metal layer that is a plating layerfixed on the resin layer, and the metal layer is not present on a regionof the resin layer that is located in the at least one first opening ofthe magnetic metal body.
 19. The vapor deposition mask according toclaim 15, wherein: the resin layer is produced by forming a resin filmhaving a tensile stress of greater than 0.2 MPa at room temperature in asubstrate, and then securing the resin film onto the magnetic metalbody, followed by removing the substrate from the resin film, and theresin layer and the magnetic metal body is secured on the frame while astep of stretching the resin layer and the magnetic metal body in apredetermined layer in-plane direction is not performed.
 20. A methodfor manufacturing an organic semiconductor device comprising the step ofvapor-depositing an organic semiconductor material on a work using thevapor deposition mask of claim 15.